(on reassignment).
[¶ 1.] Defendant Jason Castleberry was convicted of felony possession of marijuana. He contends that the evidence against him was illegally seized in the search of his vehicle. Because he gave a valid consent to search, we affirm the trial court’s denial of his motion to suppress.
Background
[¶ 2.] At 2:16 A.M., on July 2, 2002, Rapid City Police Officer Christopher Hansen stopped defendant for speeding on Interstate 90. He had been traveling 75 miles per hour in a zone where the posted speed limit was 65 miles per hour. When the officer walked up to the car, defendant was holding his driver’s license and vehicle rental agreement out the window. Hansen had defendant accompany him to the patrol car. While checking defendant’s driving history with the dispatcher and typing defendant’s information into the computer, Hansen continued conversing with defendant. He asked, “If a drug dog were to walk around the outside of your vehicle, would there be any reason that it would alert to the scent of drugs coming from within your car?” Defendant paused for awhile, looked away, and said, “um, no.” What happened next is disputed.
[¶ 3.] Hansen testified that he asked for and received defendant’s consent to search the car. Defendant denied giving his consent. In any event, after receiving the claimed consent, Hansen placed defendant in the back seat of the patrol car and searched the passenger compartment, finding drug paraphernalia and marijuana. Defendant was handcuffed and placed under arrest. Another officer arrived and Hansen had him search defendant’s trunk. Several large duffel bags containing marijuana were found. In total, the officers discovered 66.3 pounds of marijuana.
[¶ 4.] Defendant moved to suppress the evidence seized from his car on the grounds that the officer had extended the traffic stop without reasonable suspicion and that while defendant was illegally detained he refused to consent to a search.
*386After a hearing, the circuit court ruled that the facts did not support reasonable suspicion, but that while defendant was legally detained he freely and voluntarily consented to a search of his vehicle. In his written findings, however, the judge decided (inconsistent with his earlier ruling) that both probable cause existed for the search and that defendant had consented to the search. In a court trial, the judge found defendant guilty of possession of marijuana. On appeal, defendant challenges the circuit court’s findings on probable cause and consent. Because we conclude that defendant consented to the search during a lawful traffic stop, we need not address his other assertion of error.
Analysis and Decision
[¶ 5.] Defendant first contends that Officer Hansen had no legal reason to expand the stop in order to seek defendant’s consent, and therefore, “consent, if obtained at all, was necessarily involuntary.” However, during the hearing, on this specific point, the circuit court asked Hansen: “Do you recall? When you asked him that question, do you know if you were in the process of writing the ticket or whether you’ve completed writing the ticket?” In response the officer stated:
While I’m speaking with him, I’m typing information into the computer for a license check and that information comes back as information I need to write down on the ticket. And it was somewhere in there I asked those questions.
The court later inquired further:
The Court: Prior to the permission being granted, would there have been a gap of time between the ticket and the granting of permission? Could you recall any activity that occurred or anything that would have happened between those two time frames?
The Witness: Now, the only thing that I can remember is that while I’m filling out the ticket, I’m talking with him and I’m waiting for information back on the terminal because I have to use some of that information to fill in on the ticket. So as I’m waiting for that information, I’m asking these questions and I do remember that once he gave me permission to search, I got outside of my car, called for another officer to help me and I can’t remember if my ticket was completed or not.
With these responses, we cannot say that the court erred in concluding that “[d]ur-ing the course of issuing a warning citation and checking the defendant’s license status, the officer asked for defendant’s consent to search the vehicle.”
[¶ 6.] In asserting error in the court’s finding of consent, defendant points to inconsistencies in Officer Hansen’s reports and testimony as well as other factors. Hansen’s report, affidavit, and trial testimony reflect different versions of defendant’s alleged consent to search. In the application for the search warrant, Hansen wrote that defendant responded to his request to search the vehicle with “Um, yeah, why, did you smell something?” In the police report, Hansen stated that defendant responded, “Um, well, sure, why did you smell something?” At the preliminary hearing, Hansen testified that defendant’s response “was somewhat hesitant and then saying yes that I could search his vehicle and then he asked if I had smelled something.” But under cross-examination, Hansen admitted that defendant did not say, “yes, you can search my vehicle”; rather, he believed his affidavit more accurately reflected defendant’s words. At the suppression hearing, Hansen agreed that he characterized defendant’s response as hesitant. Defendant testified that he did not give consent and only answered the *387officer’s inquiry by the question, “Why, did you smell something?”1
[¶ 7.] Defendant also points to other discrepancies in Officer Hansen’s testimony. Hansen was asked if he commented to defendant that the department received funding for using drug detection dogs. He denied this. Defendant testified that when he asked Hansen why he wanted to search the vehicle, Hansen’s response was that department funding was tied to the number of drug searches officers do. Hansen was again questioned about this comment and admitted that he mentioned “our department likes to see our efforts of drug interdiction and there are opportunities for departments to receive funding for new equipment, any type of equipment, due to those efforts.”
[¶ 8.] Under the Fourth Amendment to the United States Constitution and Article VI of the South Dakota Constitution, unreasonable searches are prohibited. Searches conducted without a warrant are unreasonablé unless an exception applies, such as consent. Schneckloth v. Bustamonte, 412 U.S. 218, 219, 93 S.Ct. 2041, 2043-44, 36 L.Ed.2d 854 (1973). Here, the officer testified that defendant consented to a search of his rental car. Defendant testified that he never consented. After hearing the testimony of both defendant and the arresting officer, the circuit court believed the officer. Based on the record before us, we cannot say that the. court’s findings were clearly erroneous.
[¶ 9.] To determine whether a consent to search was freely and voluntarily given, the totality of the circumstances surrounding the consent must be examined. Id. at 227, 93 S.Ct. at 2047-48. In viewing the totality of the circumstances, we consider the characteristics of the accused: age, maturity, education, intelligence, and experience. We also consider the conditions wherein the consent was obtained, including the officer’s conduct and the duration, location, and time of the event. United States v. Watson, 423 U.S. 411, 424, 96 S.Ct. 820, 828, 46 L.Ed.2d 598 (1976). Whether the accused knew that he possessed a right to refuse consent also is relevant to ■ determining the voluntariness of the consent, although the State need not prove that defendant knew of the right to refuse consent to show that the consent was voluntary. Schneckloth, 412 U.S. at 248-49, 93 S.Ct. at 2059; see also United States v. Drayton, 536 U.S. 194, 122 S.Ct. 2105,153 L.Ed.2d 242 (2002).
[¶ 10.] The wording in a law enforcement officer’s question for consent is also relevant. For example, in a case where an officer asked a person whether he hád anything illegal in the vehicle and then asked “Do you mind if I take a look?” the response was “Sure.” The court found that “Sure” “convey[ed] the lack of consent, as in ‘Sure, I mind.’ ” United States v. Barrington, 210 FSupp2d 773, 778 (2002).2 However, “[c]onsent can be inferred from words, gestures, and other conduct.” United States v. Jones, 254 F.3d 692, 695 (8th Cir.2001). In Jones, the court wrote, “[t]he precise question is not whether [defendant] consented subjectively, but whether his conduct would have caused a reasonable person to believe that he consented.” Id. at 695. Further, “[t]he State’s burden is not met ‘by showing a mere submission to a claim of-lawful au*388thority.’ ” State v. Zachodni, 466 N.W.2d 624 (S.D.1991) (quoting Florida v. Royer, 460 U.S. 491, 497, 103 S.Ct. 1319, 1324, 75 L.Ed.2d 229 (1983)).
[¶ 11.] Whether the Fourth Amendment was violated is a de novo question on appeal. Ornelas v. United States, 517 U.S. 690, 699, 116 S.Ct. 1657, 1663, 134 L.Ed.2d 911 (1996); State v. Hirning, 1999 SD 53, ¶ 9, 592 N.W.2d 600, 603. On the other hand, the voluntariness of consent search is a factual question, and as a reviewing court, we must affirm the circuit court’s factual findings unless we conclude that they were clearly erroneous. State v. Guthrie, 2001 SD 61, ¶ 56, 627 N.W.2d 401, 423 (citation omitted); cf. United States v. Alverez, 235 F.3d 1086, 1088 (8th Cir.2000) (“We review for clear error the district court’s findings of fact and de novo its determination that the Fourth Amendment was not violated.”)
[¶ 12.] Here, there were some inconsistencies in the arresting officer’s testimony. Nonetheless, the circuit court weighed all the facts to conclude that there was a voluntary consent. When a court “bases a finding of consent on the oral testimony at a suppression hearing, the clearly erroneous standard is particularly strong since the [court] had the opportunity to observe the demeanor of the witnesses.” United States v. Sutton, 850 F.2d 1083, 1086 (5th Cir.1988). Even if we were convinced that the opposite finding would have been made had we been the fact finders, we cannot reverse the circuit court finding “that consent was given voluntarily unless” we can say “that the view of the evidence taken by the” court was “implausible in light of the entire record.” United States v. Lattimore, 87 F.3d 647, 651 (4th Cir.1996) (citing Anderson v. City of Bessemer City, N.C., 470 U.S. 564, 573-74,105 S.Ct. 1504,1511-12, 84 L.Ed.2d 518 (1985)).
[¶ 13.] In reviewing the totality of the surrounding circumstances, we detect nothing implausible about the circuit court’s findings. On the date of the search, defendant was twenty-three years old and had prior experience with the legal system. He was no “newcomer” to the law. Watson, 423 U.S. at 424-25, 96 S.Ct. at 828. Nothing in the record indicates that a coercive or intimidating atmosphere induced him to act against his will. He was stopped in the early morning hours for speeding on Interstate 90. Defendant apparently knew the procedure because as the officer approached his rental car, defendant was already holding out his driver’s license and other papers. Defendant accompanied the officer back to the patrol car to receive a warning citation.
[¶ 14.] In the course of this brief stop and following routine questioning, defendant gave his consent to search the car. Defendant said either “Um, yeah, why, did you smell something?” or “Um, well, sure, why did you smell something?” Although not recalling the exact wording, the officer testified consistently that defendant gave his consent. Hansen reported that on the way to the patrol car, defendant asked if he “could get a warning and be on his way.” While in the patrol car he asked, “ ‘Is all this necessary, can I just get a warning and go?’ ” (Hansen’s affidavit). Defendant “again asked if all this was necessary and if he could just get a warning” (Hansen’s report). The trial court found that defendant’s hesitant response was “Um, yeah, why, did you smell something?” Based on this response, the court found voluntary consent. Furthermore, as the trial court noted, defendant made no protest while his vehicle was being *389searched.3 See State v. Sheehy, 2001 SD 130 ¶ 12, 636 N.W.2d 451, 454. Based on this record, the conclusion that defendant’s oral consent was given voluntarily is adequately supported. Thus, the circuit court’s denial of defendant’s motion to suppress must be upheld.
[¶ 15.] We have heretofore held .that where the State relies on consent to conduct a search, it has the burden to prove by clear and convincing evidence that the consent was valid. State v. Almond, 511 N.W.2d 572, 574 (S.D.1994) (citations omitted). To bring ourselves into conformance with Supreme Court Fourth Amendment standards for reviewing consent searches, we have recently adopted the preponderance of the evidence analysis and abandoned our old clear and convincing ■ standard. State v. Akuba, 2004 SD 94, 686 N.W.2d 406; see also United States v. Matlock, 415 U.S. 164, 177-78, 94 S.Ct. 988, 996, 39 L.Ed.2d 242 n14 (1974) (burden on prosecution to show voluntariness of consent to search). This is the burden used consistently with other prosecution burdens on similar issues. Colorado v. Connelly, 479 U.S. 157, 167-69, 107 S.Ct. 515, 522-23, 93 L.Ed.2d 473 (1986) (same burden on prosecution to show defendant waived Miranda rights); Nix v. Williams, 467 U.S. 431, 444, 104 S.Ct. 2501, 81 L.Ed.2d 377 (1984) (burden to show inevitable discovery of evidence obtained by unlawful means); Lego v. Twomey, 404 U.S. 477, 484, 92 S.Ct. 619, 624, 30 L.Ed.2d 618 (1972) (prosecution must prove at least by a preponderance of the evidence that confession was voluntary).
[¶ 16.] Affirmed.
[¶ 17.] GILBERTSON, Chief Justice, and ZINTER, Justice, concur. [¶ 18.] SABERS and MEIERHENRY, Justices, dissent.. No recording of the arrest or conversation was made.
. In United States v. Price, the court was faced with the same question and response as in Barrington, but the Price court found that "Sure” was ambiguous and could be "interpreted as either 'Go ahead' or 'No way.' ” 54 F.3d 342, 346 (7th Cir.1995).
. Hansen testified that he based consent solely on the statement, "Um, yeah, why, did you smell something?” but he also admitted this statement was given hesitantly.